Genetic evidence suggests a causal relationship linking thyroid function to osteomyelitis.

OBJECTIVE

The causal relationship between thyroid dysfunction and osteomyelitis was unclear. The authors used two-sample Mendelian Randomization (MR) methods to investigate the potential causal effects of hyperthyroidism and hypothyroidism on the risk of osteomyelitis.

METHOD: The authors obtained summary-level data from large-scale genome-wide association studies for hyperthyroidism, hypothyroidism, and osteomyelitis for individuals of European ancestry. The causal analysis between thyroid dysfunction and osteomyelitis was carried out using Univariable MR (UVMR). Subsequently, Multivariable MR (MVMR) was performed to adjust for potential confounding from years of schooling, smoking initiation, and body mass index. A range of sensitivity analyses, including reverse MR, was conducted to test the robustness of the results.

RESULTS

In univariable analysis, genetically predicted hyperthyroidism (Odds Ratio [OR = 1.21], 95% Confidence Interval [95% CI 1.071‒1.374], p = 0.002) and hypothyroidism (OR = 1.140, 95% CI 1.035‒1.255, p = 0.0078) were both associated with an increased risk of osteomyelitis. After adjusting for confounders in the MVMR analysis, the association for hyperthyroidism was attenuated to non-significance (OR = 1.07, 95% CI 0.95‒1.21, p = 0.28). In contrast, the causal effect of hypothyroidism on osteomyelitis remained robust (OR = 1.15, 95% CI 1.03‒1.29, p = 0.02). Reverse MR analyses showed no evidence that osteomyelitis was a cause of either hyperthyroidism or hypothyroidism.

CONCLUSION

This study provided genetic evidence supporting a causal effect of hypothyroidism on an increased risk of osteomyelitis. This finding provides evidence-based recommendations for closely monitoring patients with hypothyroidism to prevent the onset of osteomyelitis.